Large heading text
Normal body text at 16px. The quick brown fox jumps over the lazy dog, testing legibility at typical reading size.
Small caption text at 12.8px — the hardest to read.
Color-blindness check
Frequently asked questions
What contrast ratio does WCAG require?
WCAG 2.2 AA requires 4.5:1 for normal text and 3:1 for large text (18pt+, or 14pt bold) and UI components. AAA raises these to 7:1 and 4.5:1.
How is the contrast ratio calculated?
It compares the relative luminance of the two colors using the WCAG formula (L1 + 0.05) / (L2 + 0.05), producing a ratio between 1:1 and 21:1.
What if my colors fail?
The tool automatically suggests the nearest shade of your text color that passes AA — click Apply to use it.
Does this cover color blindness too?
Yes — every check includes a simulation of your color pair under protanopia, deuteranopia, tritanopia and achromatopsia, with recalculated ratios.